Ancient Tooth Shows Oldest Sign of Dentistry

Italian researchers believe they have discovered the oldest dental filling — a beeswax cap applied to a left canine tooth about 6,500 years ago.

The filling was discovered by chance as Claudio Tuniz, Federico Bernardini and colleagues at the Abdus Salam International Center for Theoretical Physics in Trieste used a fossilized jaw bone to test new X-ray imaging equipment.

Found early last century embedded on the wall of a karstic cave near the village of Lonche, in what is now Slovenia, the bone most likely belonged a 24–30-year-old individual.

The analyses showed a filled vertical crack in the hard enamel and softer dentin layers of the tooth. Infrared spectroscopy identified the filling material as beeswax.

Radiocarbon dating then established that both the filling and the tooth were about 6,500 years old, suggesting that the treatment was done shortly before or after the individual’s death.

The severe wear seen on the tooth was probably due “to its use in non-alimentary activities, possibly such as weaving, generally performed by Neolithic females,” Tuniz said.

Although the researchers could not rule out the possibility that the beeswax was added during a funerary ritual and that the tooth cracked as it dried out in the cave’s wall, they believe the hypothesis is rather unlikely.

“Other teeth have exposed dentin but no beeswax was applied. This suggests that the canine caused particular discomfort during life. Concerning a possible post-mortem application of the beeswax, one could wonder why it was applied only on the exposed dentin of the canine,” the researchers wrote in the journal PLOS ONE.

Moreover the SEM images show that beeswax was probably deposited on the tooth when the crack was already formed “since the chippings on the edges of the fracture were sealed by the beeswax,” Tuniz and Bernardini said.

The researchers believe the treatment was likely aimed to relieve tooth sensitivity derived from either exposed dentine and the pain resulting from chewing on a cracked tooth.

“This would provide the earliest known direct evidence of therapeutic-palliative dental filling,” Bernardini and Tuniz concluded.